Abrasion resistant package of wound asphaltic material of construction

ABSTRACT

This invention relates to a package comprising a roll of asphaltic roofing or siding material wrapped with a stressed polymeric membrane having an elasticity of at least 4%.

BACKGROUND OF THE INVENTION

[0001] Currently, rolls of petroleum based products which are manually wrapped in craft paper and/or secured with scotch tape are subject to abrasion and tearing during shipment and storage. Often damaged rolls are returned to the manufacturer and must be sold at an insupportable discount or discarded as waste. Accordingly the weight of the roll is restricted by the strength of the paper wrapper. Further, manual wrapping causes a bottleneck in wrapped product production since the wound rolls are generally produced at a speed of up to 12 rolls/minute; whereas only 3-4 rolls/minute can be achieved by manual wrapping. These factors have led to serious losses in the manufacture of BUR roofing, wound rolls of laminate and other rolled asphaltic material employed in many areas of construction.

[0002] Accordingly, it is an object of this invention to eliminate or minimize the above problems in an economical, commercially feasible manner and to provide an improved product resistant to varying climatic conditions.

[0003] Another object is to provide a process for accomplishing the above aims and to provide a package of added strength.

[0004] Still another object is to provide a more compact, abrasion and tear resistant package of rolled asphaltic material.

[0005] Yet another object is to provide a damage resistant wrapping capable of handling heavier loads of rolled material.

[0006] Still another object is to provide an improved means of handling and using the packaged rolls of asphaltic material.

[0007] These and other objects and advantages will become apparent from the following description and disclosure.

SUMMARY OF THE INVENTION

[0008] This invention applies to the wrapping of any material of construction produced in rolls and comprises a roll of material at least partially wrapped in a stressed elastic polymeric film or membrane having an elasticity of at least 4%.

DETAILED DESCRIPTION OF THE INVENTION

[0009] Rolls of asphaltic based construction materials can be produced in a wide range of weights and widths varying between about 45 and about 120 pound rolls having widths of from about 12 inches to about 10 feet. For example, asphaltic sheeting material used in BUR roofing is desirably produced in weights of from about 70 to about 90 pounds per roll and in widths of 10 to 36 inches; whereas asphalt based laminates or strips for sidings, shingle backers and other uses generally are produced in rolls of about 80 to about 90 pounds having a width of from about 12 to about 32 inches. The techniques of winding such materials are well known and are conventional.

[0010] In accordance with the present invention, rolls of asphaltic material, eg RUBEROID®, BUR, eg. GAFGLAS® felts etc. are subjected to exterior wrapping with an elastic polymeric film or membrane under stressed, i.e. stretched, membrane conditions. The wrapping membrane comprises a polymer of ethylene, propylene, vinyl chloride, or other organic polymer having an elasticity of at least 4%, preferably an elasticity of from about 5 to about 25%. Most preferred membranes include polypropylene and polyethylene of 10-20% elasticity.

[0011] The wrapping is employed to at least partially enclose the roll. For example, the membrane can completely cover the roll to protect it from abrasion during handling and storage. Alternatively, the wrapper may enclose only a portion of the roll's circumference to maintain its integrity and to prevent expansion of the wound layers. In the later case, the width of the partial wrapper membrane is at least 10^(th) the width of the roll; for most uses, a membrane width of ¼^(th) to ¾^(th) the width of the roll at its midsection is adequate to achieve the desired purpose. Optionally, the plastic wrapper may include at least one releasable seam or side slit for ease of removal prior to installation of the asphaltic based material. Suitable seams can be provided for example by a plurality of easily separated perforations, embossments or an embedded tear tape disposed across the width of the membrane. Another wrapper option includes a free flap or tab extending horizontally above the wrapped roll; said flap may additionally include grasping or carrying means such as a cut out area or an additional flap extension defining a handle. The flap of the wrapper may also include an anti-displacement bar or protuberance of cellulosic, cardboard, compressed paper or plastic material to provide a ridge which prevents the wrapped product from rolling.

[0012] It will be understood that the thickness of the wrapper is commensurate with the weight of the roll so that the membrane is stretched but does not split or break during and after packaging the roll. Hence, membranes of from about 0.5 to about 10 mils thickness are suitably employed.

[0013] The wrapping membrane can also be adapted to portray contrasting color and/or printed matter, e.g. to indicate product identification, recommended use or warning, manufacturer designation, proprietary interests and/or other desirable information.

[0014] The packaged roll of the invention is comprised of a continuous sheet of asphaltic material wound upon itself and optionally containing a cellulosic or plastic core at its center. BUR roofing usually comprises asphaltic sheeting weighing between about 45 and about 120 lbs (more often 70-90 lbs.) and has a width of from about 20 to about 100 inches. A wrapping membrane thickness of 1-4 mils is recommended for packaging such BUR material.

[0015] The present abrasion and tear resistant wrapper, being stronger than conventional craft paper wrappings and more protective than sealing tape, is able to accommodate heavier and larger loads of wound asphaltic material. Further, the present plastic wrapping procedure is conducive to in-line mechanical operation between the asphalt winding and wrapping zones thus eliminating the previous hold-up due unmatched speeds of wound roll production and manual wrapping. Because of the stressed or expanded condition of the wrapper around the roll and the inherent recovery memory of the plastic, the wrapper compresses the winding and is not displaced from its original position on the roll. Thus a more compact package is provided. Preferably the weight of the wound material alone is employed to stretch the polymeric wrapper; although extraneous tension means may augment the degree of stretch.

[0016] Having described the invention in general terms, reference is had to the accompanying drawings which illustrate preferred embodiments; however, these embodiments are not to be construed as limiting to the scope of the invention as more broadly defined above and in the appended claims. FIGS. 1 and 2 are schematic illustrations of the wound roll before and after wrapping with the elastic polymeric membrane. FIG. 3 is a perspective view of a preferred wrapped product.

[0017] The manufacture of the present wrapped product is accomplished in an economical, time saving manner using in-line mechanical winding and wrapping operations. The sheet of asphaltic material is rolled or wound in a conventional manner at a winding station. Referring to the schematic representation in FIG. 1, prior to wrapping, a wound roll of material 4 from winding station 2, is passed in horizontal position to holding zone 6 which is defined by 2 horizontally disposed, laterally movable retaining means 8 and 8 a in closed position. Holding zone 6 is positioned above a curtain of elastic polymer film 11, which is supported by spaced support members 10 and 10 a. Elastic film 11, which is supplied from plastic polymer film rolls 14 and 14 a, is disposed horizontally on a plane perpendicular to roll 4. Located below film curtain 11 are laterally movable sealing and cutting bars 12 and 12 a disposed in open non-engaging position.

[0018] In FIG. 2, movable retaining means are opened outwardly, permitting wound roll 4 to drop onto film curtain 11. The weight of the roll stretches the film and causes the expanded film to engage the bottom and side portions of the roll whereupon heat sealing bars 12 and 12 a are moved inwardly toward each other and engage the outer surface of film 11 immediately above roll 4 to completely encompass and to seal the stretched film around roll 4 to form the compact product package of the invention.

[0019]FIG. 3 illustrates a preferred embodiment of the polymeric film wrapped package of the present invention. In the drawing, elastic film 40, carrying color contrasted printed matter 48, is stretched and sealed around the midsection of roll 4. The sealed section has precut tear incision 46 to facilitate wrapper removal. It will be understood that other separation means such as a perforated seam, an embedded tear strip or other means can be employed for easy wrapper removal. Above the seal, free tab extension 49 extends over the width of the wrapper and is provided with cutout grasping means 47 to provide ease of handling.

[0020] The above descriptions illustrate preferred embodiments but are not to be construed as limiting the invention as it will become apparent that many modifications and additions can be made in the above figures without departing from the scope of this invention. For example, the tab can be modified to carry one or more nodes, protrusions or retaining means such as a retaining bar to prevent rotational displacement of the wrapped roll during storage or when placed for installation on an inclined roof. Many other alterations and substitutions will become apparent and are considered within the scope of this invention. 

What is claimed is:
 1. A packaged material of construction comprising a roll of asphaltic roofing or siding material and a polymeric membrane or film having an elasticity of at least 4% wrapped in stressed condition around the circumference of said roll to provide a compact, damage resistant wrapped product.
 2. The package of claim 1 wherein the thickness of said membrane is commensurate with the weight of said roll to allow stretching without breaking the membrane.
 3. The package of claim 2 wherein the thickness of the membrane is between about 0.5 and about 10 mils.
 4. The product of claim 1 wherein the elastic membrane is selected from the group consisting of a polymer of propylene, ethylene and vinyl chloride.
 5. The product of claim 4 wherein the elastic membrane is poly(propylene).
 6. The product of claim 1 wherein the elastic membrane has an elasticity of from about 5 to about 25%.
 7. The product of claim I wherein said roll of asphaltic material is a roll of built up roofing material.
 8. The product of claim 1 wherein said elastic membrane is stretched between about 5 and about 20% around said roll.
 9. The product of claim 1 wherein said membrane totally encases the roll of asphaltic material.
 10. The product of claim 1 wherein said membrane partially encloses at least {fraction (1/10)}^(th) the width of said roll of asphaltic material.
 11. The product of claim 1 wherein the roll of asphaltic material has a weight of between about 45 and about 120 pounds.
 12. The product of claim 11 wherein the roll of asphaltic material has a weight of between about 70 and about 90 pounds.
 13. The product of claim 1 wherein said wrapped product carries a freely movable flap extension equipped with at least one cut out area for holding or carrying the wrapped roll.
 14. The product of claim 1 wherein the wrapped portion of said elastic membrane has an easily separable seam across its width or a precut incision located on at least at one side edge of the film.
 15. The product of claim 13 wherein said tab extension carries at least one protuberance below said cut out area to prevent rotation of the roll.
 16. The process for producing the product of claim 1 which comprises: (a) introducing, in a horizontal position, a roll of asphaltic roofing or siding material having a weight of between about 45 and about 120 pounds into a roll retaining area; (b) releasing the roll from said retaining area; (c) allowing the horizontally positioned roll to drop by gravitational force onto a membrane of elastic film having an elasticity of at least 4%; said membrane, located beneath said retaining area and horizontally posttioned on a plane perpendicular to that of the roll, said membrane having a thickness sufficient to stretch without breaking when the weight of the roll is contacted; (e) stretching the membrane around the roll while sealing the stretched sides of the membrane and (f) recovering the resulting roll enwrapped in the stretched membrane as the product of the process.
 17. The process of claim 16 wherein the membrane is stretched around ¼^(th) to ¾^(th) the midsection of said roll.
 18. The process of claim 16 wherein the membrane has an elasticity of between 5 and about 25%.
 19. The process of any one of claims 16, 17 and 18 wherein the membrane has a thickness of from 0.5 to 10 mils.
 20. The process of claim 16 wherein the roll of asphaltic material is a roll of roofing material.
 21. The process of claim 16 wherein the sealed portion has means for easy membrane separation selected from the group of a plurality of separable perforations, embossments, a release strip across its width and a precut incision at a free leading or trailing side edge of the membrane.
 22. The process of claim 16 wherein the wrapped roll is separated after sealing by cutting the membrane at a distance away from said sealing operation to provide a graspable tab freely extending from the wrapped roll product.
 23. The process of claim 22 wherein said tab contains a graspable cut out section. 